1. Field of the Invention
The present embodiments relate to methods, systems, and programs for managing read and write requests in a storage system.
2. Description of the Related Art
Network storage, also referred to as network storage systems or storage systems, is computer data storage connected to a computer network providing data access to heterogeneous clients. Typically network storage systems process a large amount of Input/Output (IO) requests, and high availability, speed, and reliability are desirable characteristics of network storage.
Some network storage devices have hard drives and solid state drive (SSD) drives, and are referred to as hybrid storage systems. Other, more recent, network flash storage devices include only SSD drives. Existing kernel IO schedulers are not well suited for SSD-only storage devices because SSD drives have unique characteristics that are different from traditional hard drives. For example, in SSD drives, the write latency is usually several orders of magnitude greater than the read latency (e.g., 5 to 1, 10 to 1). This means that multiple pending write requests of the size that the user has given can increase the read latency significantly.
What is needed is a network storage device having SSD drives with schedulers that minimize the read latency and maximize the write throughput.
It is in this context that embodiments arise.